What Do the Authors Recommend That Teachers Do to Manage

What do the authors recommend that teachers do to manage e-mail correspondences with parents or guardians?

A) use their personal e-mail to correspond with parents and guardians.
B) establish and inform parents and the school administration of their policy for answering e-mail.
C) delete all emails from parents or guardians within 24 hours of responding.
D) promise to respond to parents or guardians within a couple of hours of receiving an email.